ABILITY OF THE NO-REFLOW PHENOMENON DURING AN ACUTE MYOCARDIAL-INFARCTION TO PREDICT LEFT-VENTRICULAR DYSFUNCTION AT ONE-MONTH FOLLOW-UP

Despite angiographically successful opening of an infarct-related vessel within a 6-hour time frame, some patients do not do not recover left ventricular regional wall myocardial infarction (AMI). Recent evidence suggests that this finding is due to the no-reflow phenomenon, or failure to recover tissue perfusion despite patent epicardial arteries. We performed myocardial contrast echocardiography to assess tissue perfusion before and after opening of an infarct-related artery. Coronary angiograms, regional wall motion scoring, and myocardial contrast enhancement were graded by 3 observers. Of 24 patients with AMI, 7 (29%) failed to recover tissue perfusion in greater than or equal to 1 region of myocardium. Of 106 regions subtended by the infarct-related artery, 16 (15%), 43 (41%), and 47 (44%) regions had no-reflow, partial, or normal flow, respectively, after arterial patency was established. There was a spectrum of reperfusion patterns ranging from no-reflow to normal perfusion. One-month follow-vp angiographic and myocardial contrast echocardiographic studies were performed in 12 of the 24 patients. At 1 month, all segments of myocardium that had immediate normal perfusion had regained normal wall motion. In contrast, 17 segments that had partial or no-reflow were identified. Of these 17, 3 regained normal function, 10 segments were hypokinetic, and 4 segments were akinetic. We conclude that myocardial contrast echocardiography can be used to identify the no-reflow phenomenon in up to 29% of patients with AMI. Additionally, we found that the immediate-reflow pattern can predict degree of left ventricular dysfunction at 1-month follow-up.